In modern communication networks, particularly in motor vehicles, bus systems such as CAN, LIN or Flex Ray may be used. A plurality of control units may thereby be connected to one another. In this context, such bus systems are configured for the cost-effective transmission of signals between the control units.
To secure the transmission from errors, redundancies are fitted into the signal flow, so that corruptions may be detected on the receiver side. It is possible, however, to import messages into the bus system in a targeted manner, by connecting using a special bus node, such as a laptop having a CAN interface. Such incorporated outside messages are not detectable in the related art or only at great expenditure. Even detecting an outside control unit in the communication system is not possible.
It is therefore desirable to state a possibility of detecting a manipulative change of a communication system in a simple manner.